Conventional drive arrangements for two-axle earth moving machines comprise a diesel engine which is connected via a hydrodynamic torque converter with the input shaft of a gear box, whose output shaft is connected via spur gearing with the universal joint shaft as a driving connection. Drive systems of this type not only have an unfavorable draft, that is, load or load-pulling capacity, characteristic but also due to rigid coupling of the internal combustion engine, which is usually a diesel engine, via the hydrodynamic converter, the gear box and the spur gearing, to the universal joint shaft is elaborate and disadvantageous.
Certain improvements in drive arrangements of the type in question are possible, provided the internal combustion engine is connected through a hydraulic pump which drives a hydrostatic motor whose power may be controlled and whose output shaft is arranged to drive the universal joint shaft via a gear box. Such a drive system is not only more adaptable due to the connection of the hydraulic pump with the hydrostatic motor using a hydraulic hose or hoses, but, it also makes it possible to use a hydrostatic drive arrangement and, as well, provide a closer approach to the ideal curve of the draft function, that is to say the draft as a function of speed.
It is an object of the invention to provide a drive arrangement of the initially described type having a simplified structure and which is adaptable to requirements arising in use in an advantageous manner.
It is still a further object of the invention to provide a drive arrangement of the initially described type which exhibits ready accessibility for servicing.